title: Endoscopic ultrasonographic evaluation of the esophagus in healthy dogs.
abstract: OBJECTIVE
  To characterize the ultrasonographic appearance of the canine esophagus.
  
  
  METHODS
  14 healthy Beagles.
  
  
  METHODS
  Endoscopic ultrasonography (EUS) examinations were performed with a radial ultrasonographic gastrovideoscope in anesthetized dogs. Images were obtained at 3-cm intervals along the esophageal length to allow evaluation of the esophageal wall. Images were obtained with the probe in direct contact with the esophageal wall and with a water-filled balloon as a standoff.
  
  
  RESULTS
  Images were obtained with (12 dogs) and without (10) the water-filled balloon. Median thickness of the esophageal wall was 2.19 mm (range, 1.03 to 5.62 mm) in the proximal third of the esophagus, 2.15 mm (range, 1.10 to 4.45 mm) in the middle third, and 2.84 mm (range, 1.35 to 5.92 mm) in the distal third. Wall thickness differed significantly between proximal and distal thirds. Results were similar when the water-filled balloon was used. Esophageal wall layers appeared as 5 alternating hyperechoic and hypoechoic bands that could not be consistently identified in all dogs. All layers could be identified in 26 of 198 (13%) images, 3 layers could be identified in 67 of 198 (34%) images, and 105 of 198 (53%) images had no layers. Visual identification of layers in images obtained with and without the balloon did not differ significantly.
  
  
  CONCLUSIONS
  EUS appeared to be a useful technique for assessing esophageal wall integrity in dogs; however, complete evaluation of all layers could not be accomplished in all instances. Further studies with this technique in dogs are needed.
authors.affiliation: Division of Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, CH-8057, Zurich, Switzerland.
authors.forename: Penelope A
authors.initials: PA
authors.lastname: Baloi
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Kircher
authors.forename: Peter H
authors.initials: PH
authors.lastname: Kook
mesh_terms: D000818:Animals; D004285:Dogs / Q000033:anatomy & histology*; D019160:Endosonography / Q000379:methods / Q000662:veterinary*; D004947:Esophagus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D008297:Male